I have no idea.
My Sub18 has energy like no other direct radiator sub I have including the JBL 5749’s.
I should say that I use a Crown ITECH 5000HD bridged on it. Thats a lot of power.
My personal favorite, the best bass I have are my Community Boxer Bass Horns on my patio. These big front loaded horns are it for me.
Barry.
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I play bass guitar, so I do appreciate a bit of trouser-flapping low frequency. About 30 years ago, I built some transmission line speakers based on the IMF TLS-80, with B139s and B110A, then B mids, but with metal dome tweeters and super tweeters. They are huge and heavy, although just about acceptable in a domestic situation. I still use and enjoy them today. Cambridge R50s, Linn Isobariks and TDLs often come up for sale on the cheap and this seems like a good way to get cheap, deep bass.
I heard some Urei 813 speakers in a recording studio and loved how they sounded in the bass. I then had the luck to own a pair, but they sounded relatively awful in my home situation. I guess their requirement for "soffit mounting" mattered. I had to sell them unfortunately, before I could get them to sing. They were impossibly large, even in comparison to my own transmission lines.
I heard some Urei 813 speakers in a recording studio and loved how they sounded in the bass. I then had the luck to own a pair, but they sounded relatively awful in my home situation. I guess their requirement for "soffit mounting" mattered. I had to sell them unfortunately, before I could get them to sing. They were impossibly large, even in comparison to my own transmission lines.
I don't agree. There's not a huge amount of material with content down there, but enough now that I've owned, and heard, other systems with the capacity to do it well, I wouldn't forgo it in a system I built. Even well recorded classical symphonic works can have a useful difference here. It's not just me either as my friend Terry's large system has been heard by many at his GTGs and I've heard the comments on it. Of course you need the componentry above the LF to be able to keep up as well.
This is the thing... if the bass (and everything else) is balanced and complete (not easy to do), then you'll be satisfied even if the rolloff happens in the mid thirties.
With normal speaker placement in normal listening rooms you very often get big SBIR/lambda/4 cancellation problems in the 80-200Hz area! I had setups myself with 2 big holes and nearly no energy in this range. With a speaker a little less than a meter from the back wall and low frequency driver a little less as a meter from the floor ... you have 2 HUGE cancellations at about 100Hz.
Then the bass get's boomy and looses "snappyness". A woofer crossed over at 80Hz doesn't help at all for that - it actually can make it worse when it's setuped to loud (which it is when you do it by ear).
Low end extension is important because it lowers the frequency where the fase starts to shift fast. Look at group delay pictures of an enclosure with an f3 of 50 Hz and compare that with one with an f3 of 20 Hz. They will both reproduce 60 Hz just fine, but the latter one will have much less phase shift.
I have a single sub in a 20 m^2 untreated room (only a big sofa for treatment, which did actually improve reverb a lot), and I've found that the sub sounds best (most even response across frequency sweep) placed in a corner, with the cone and the port, which are on the same side, facing towards the wall at ~15-20 cm distance to the wall. That should be one way to completely avoid SBIR, right? But, of course, you can only do it if you have a separate sub.
But my sub is playing up to 80 Hz, and you're right that there are likely issues in the important 100-200 Hz region that is still up to the mains to play. That's a very interesting consideration.
Hi, sounds reasonable. Port and woofer direction should not make any difference on very low frequencies but for high frequencies they do. Gap between wall and the sub enclosure probably works as acoustic low pass filter reducing some harmonic distortion.
Then, for readers thinking about placing their sub on the corner as well because they've now read it works for another person. Yes, it might work for you as well but there is lot of unknowns and there is possibility its not the best place in your setup so do like Alexium did, find the best place by listening (and measuring)! Alexium post has no info about size of his room, nor about the speakers size, where are main speakers positioned, which corner is the sub at and which wall it they point at which affects SBIR. There is no info if the mains are high passed, where is crossover point, playback level and so on. Basically there is no reference what the complete system is so its about impossible to get meaningful advice to our situation, other than do what he did, just find a good location by ear and measurement.
Same goes for about all posts about anything loudspeakers, that do not have enough information about the context, about the system and about the room where the advice applies and also shared audio experience perceived to have expectations and used vocabulary to meet. This is not to blame on anyone, its just something I've noticed recently that its impossible to get good inspiration / advice in written form without quite large amount of information about context where the advice applies and where not. This is something that has misled me multiple times while reading and trying to understand things, not understanding the context where they apply. Carry on
Then, for readers thinking about placing their sub on the corner as well because they've now read it works for another person. Yes, it might work for you as well but there is lot of unknowns and there is possibility its not the best place in your setup so do like Alexium did, find the best place by listening (and measuring)! Alexium post has no info about size of his room, nor about the speakers size, where are main speakers positioned, which corner is the sub at and which wall it they point at which affects SBIR. There is no info if the mains are high passed, where is crossover point, playback level and so on. Basically there is no reference what the complete system is so its about impossible to get meaningful advice to our situation, other than do what he did, just find a good location by ear and measurement.
Same goes for about all posts about anything loudspeakers, that do not have enough information about the context, about the system and about the room where the advice applies and also shared audio experience perceived to have expectations and used vocabulary to meet. This is not to blame on anyone, its just something I've noticed recently that its impossible to get good inspiration / advice in written form without quite large amount of information about context where the advice applies and where not. This is something that has misled me multiple times while reading and trying to understand things, not understanding the context where they apply. Carry on
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Yes, I'm not at all implying that's a recipe to follow, just an anecdote. Thank you for pointing that out for other readers, tmuikku. I was myself expecting that corner placement will excite some room modes the most and should be avoided. But in reality it turned out to be one of the best options for me. But every room is different, even if they look alike.
The point of my post was to point out that you can eliminate SBIR for subs by reducing the distance between the wall(s) and the cone such that the corresponding quarter wavelength is above what the sub will be playing.
I wouldn't have tried cone facing the wall if I haven't heard about SBIR. With bass and subwoofer placement, you have to try everything and see what works best.
This, I think, is the biggest reason why a separate subwoofer is much superior to L+R speakers playing bass, even if they play down to 20 Hz or even less. You're not flexible in positioning them. My speakers play down to 27 Hz confidently (in the room), and 24-25 with a little EQ boost. But the cheap simple 8" sub I've got was a huge improvement.
The point of my post was to point out that you can eliminate SBIR for subs by reducing the distance between the wall(s) and the cone such that the corresponding quarter wavelength is above what the sub will be playing.
I wouldn't have tried cone facing the wall if I haven't heard about SBIR. With bass and subwoofer placement, you have to try everything and see what works best.
This, I think, is the biggest reason why a separate subwoofer is much superior to L+R speakers playing bass, even if they play down to 20 Hz or even less. You're not flexible in positioning them. My speakers play down to 27 Hz confidently (in the room), and 24-25 with a little EQ boost. But the cheap simple 8" sub I've got was a huge improvement.
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Yeah thats what I thought too, wanted to write about the context stuff to raise awareness of that among posters and readers in general. Trying to affect forum communication in long term
Yes, SBIR also depends on which wall you point at, is the corner behind or front of listening spot and which wall the sub is pointed at and compared to what. Also, while individual sources could have SBIR the combined response could be better so depends on where the mains are in relation and if there is any delay used, EQ, high and low pass. You've used the right method to do it, find best practical balance by experimenting.
Yes, SBIR also depends on which wall you point at, is the corner behind or front of listening spot and which wall the sub is pointed at and compared to what. Also, while individual sources could have SBIR the combined response could be better so depends on where the mains are in relation and if there is any delay used, EQ, high and low pass. You've used the right method to do it, find best practical balance by experimenting.
I don't know the actual definition of SBIR but I've interpreted it so that the listener is involved, source is between listener and boundary and reflection of that boundary. Other 5 boundaries of typical room are referred just as first reflection or early reflection, which the front wall reflection (SBIR) also is.
If the definition of SBIR is just combined response, effect of all first reflections to direct sound, then yes placing sub close enough corner takes away three of the boundaries.
I'm not sure in which context the SBIR is used. I've seen it used in near field monitor manuals and home studio speaker setup guides. Not sure if SBIR is used in subwoofer context as they typically reproduce wavelengths that are size of the room and subject to modes. I haven't not thought too much about how SBIR and modes would relate, if null of calculated SBIR would be cancelled out by a peak from mode and so on, making it relevant context only above modal region. I need to study and think it to answer better
When path length difference of direct sound and reflection to observation point is less than 1/4wl there is only constructive interference (ignoring modes). When the path length difference is 1/2 wl there is first null, and combfilter above. For example 100Hz is ~3.4m long so source within 40cm from a boundary keeps them combine constructively to any direction and more to some other directions 1/4wl is rougly 85cm and if source was between listener and wall its a round trip so 40cm does it. If woofer was 1m height and we are listening also at 1m height 3 meters away the path length of first reflection from floor is about half a meter so no dips below almost 200Hz! But, reflection from wall behind the speaker, if the speaker was 1meter away from the wall, would be 2meters as it is roundtrip towards listener and corresponding dip was two octaves below the floor bounce, around 8m wavelengt, ~50Hz. Basically, if the sub is front of you on the front wall, it could be as high as half way up the room, 1meter of from sidewall and 40cm from the front wall, depending on your room and position of listening spot and still have no dips below 100Hz from first reflections.
Or conversely, if sub box is < 40cm in dimension and tucked into a corner it doesn't matter which way it points at up to ~100Hz as any side of the box is close enough to any of the three boundaries, within 1/4wl inspected from any location.
If the definition of SBIR is just combined response, effect of all first reflections to direct sound, then yes placing sub close enough corner takes away three of the boundaries.
I'm not sure in which context the SBIR is used. I've seen it used in near field monitor manuals and home studio speaker setup guides. Not sure if SBIR is used in subwoofer context as they typically reproduce wavelengths that are size of the room and subject to modes. I haven't not thought too much about how SBIR and modes would relate, if null of calculated SBIR would be cancelled out by a peak from mode and so on, making it relevant context only above modal region. I need to study and think it to answer better
When path length difference of direct sound and reflection to observation point is less than 1/4wl there is only constructive interference (ignoring modes). When the path length difference is 1/2 wl there is first null, and combfilter above. For example 100Hz is ~3.4m long so source within 40cm from a boundary keeps them combine constructively to any direction and more to some other directions 1/4wl is rougly 85cm and if source was between listener and wall its a round trip so 40cm does it. If woofer was 1m height and we are listening also at 1m height 3 meters away the path length of first reflection from floor is about half a meter so no dips below almost 200Hz! But, reflection from wall behind the speaker, if the speaker was 1meter away from the wall, would be 2meters as it is roundtrip towards listener and corresponding dip was two octaves below the floor bounce, around 8m wavelengt, ~50Hz. Basically, if the sub is front of you on the front wall, it could be as high as half way up the room, 1meter of from sidewall and 40cm from the front wall, depending on your room and position of listening spot and still have no dips below 100Hz from first reflections.
Or conversely, if sub box is < 40cm in dimension and tucked into a corner it doesn't matter which way it points at up to ~100Hz as any side of the box is close enough to any of the three boundaries, within 1/4wl inspected from any location.
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That's exactly what my observation also was when playing around with one sub - but my room is highly dampened. Which doesn't matter a lot <100Hz and with standing waves ... cause they build also in good dampened rooms, just decay is way faster (which is a good thing of course).
SBIR: https://gikacoustics.com/speaker-boundary-interference-response-sbir/
In my country it's called lamda/4 chancellation but it should be the same. I first came in contact with it with subwoofers standing on the stage - you get a big cancellation, also open air and with distance. But this use case is simple compared to a small room ... lot's of surfaces.
I have had similar issue's. My main speakers can not produce anything below 28Hz. I have searched for a long time for a sub-woofer that could complement them to the absolute bottom. With a small as possible enclosure, and preferably no bass reflex ports. I ended up with the D7 Sub from Jamo. It's a closed case that uses Motional FeedBack (ala Philips MFB) to control the speaker. The D7 Sub complements my speakers perfectly and it goes from 1Hz to the cutoff at 30Hz.
I am not sure if you can still buy them as they have become a little bit old now, but you should at least listen to one if you find any
(It ain't pretty, but looks where not a requirement for me)
http://arqen.com/acoustics-101/speaker-placement-boundary-interference/I don't know the actual definition of SBIR but I've interpreted it so that the listener is involved, source is between listener and boundary and reflection of that boundary. Other 5 boundaries of typical room are referred just as first reflection or early reflection, which the front wall reflection (SBIR) also is.
If the definition of SBIR is just combined response, effect of all first reflections to direct sound, then yes placing sub close enough corner takes away three of the boundaries.
I'm not sure in which context the SBIR is used. I've seen it used in near field monitor manuals and home studio speaker setup guides. Not sure if SBIR is used in subwoofer context as they typically reproduce wavelengths that are size of the room and subject to modes. I haven't not thought too much about how SBIR and modes would relate, if null of calculated SBIR would be cancelled out by a peak from mode and so on, making it relevant context only above modal region. I need to study and think it to answer better
When path length difference of direct sound and reflection to observation point is less than 1/4wl there is only constructive interference (ignoring modes). When the path length difference is 1/2 wl there is first null, and combfilter above. For example 100Hz is ~3.4m long so source within 40cm from a boundary keeps them combine constructively to any direction and more to some other directions 1/4wl is rougly 85cm and if source was between listener and wall its a round trip so 40cm does it. If woofer was 1m height and we are listening also at 1m height 3 meters away the path length of first reflection from floor is about half a meter so no dips below almost 200Hz! But, reflection from wall behind the speaker, if the speaker was 1meter away from the wall, would be 2meters as it is roundtrip towards listener and corresponding dip was two octaves below the floor bounce, around 8m wavelengt, ~50Hz. Basically, if the sub is front of you on the front wall, it could be as high as half way up the room, 1meter of from sidewall and 40cm from the front wall, depending on your room and position of listening spot and still have no dips below 100Hz from first reflections.
Or conversely, if sub box is < 40cm in dimension and tucked into a corner it doesn't matter which way it points at up to ~100Hz as any side of the box is close enough to any of the three boundaries, within 1/4wl inspected from any location.
Brett, re:'I wouldn't forgo it' - great if you've got the space and the $$$, - I don't
AllenB: re:'you'll be satisfied" - for me the key is to get the right amount of BSC - for me 3-4 dB
Vacuphile: Re:'fase starts to shift' OK, but the audibility of this is debatable, particularly after the sound has been through the acoustic meat-grinder that is most listening rooms
AllenB: re:'you'll be satisfied" - for me the key is to get the right amount of BSC - for me 3-4 dB
Vacuphile: Re:'fase starts to shift' OK, but the audibility of this is debatable, particularly after the sound has been through the acoustic meat-grinder that is most listening rooms
I seem to be going out on a limb of the thread here.. but you can get saitsfying bass when the system rolls off at 70Hz, but you can't just take any speaker that rolls off at 70Hz and expect it.
I've done this experiment independently using a system that is constructed and balanced for the full spectrum in room, and applying an artificial rolloff.
There are systems that sound better when you throw a sub at them for bass reasons because they sound light on to begin with. This experiment will not show the same result in cases like this.
I've done this experiment independently using a system that is constructed and balanced for the full spectrum in room, and applying an artificial rolloff.
There are systems that sound better when you throw a sub at them for bass reasons because they sound light on to begin with. This experiment will not show the same result in cases like this.
DBA (or less affordable SBA). In a nutshell. If the room is suitable for.
https://www.audiosciencereview.com/...-low-q-subs-quasi-plain-wave-radiation.24396/
SBA). In a nutshell. If the room is suitable for.https://www.audiosciencereview.com/...-low-q-subs-quasi-plain-wave-radiation.24396/
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